1. Field of the Invention
The present invention pertains to the art of cooking appliances and, more particularly, to an infinite temperature control element for selectively operating a heating zone arranged on a cooking appliance cooktop.
2. Discussion of the Prior Art
Infinite temperature controls are known in the art of cooking appliances for controlling heating elements or zones arranged on cooktops of the cooking appliances. Typically, a control element or knob is rotated from an “off” position, across a temperature selection zone, to establish a desired operating temperature for a heating element. The temperature zone ranges from a low setting, positioned in a beginning portion of the rotation of the control knob, to a maximum setting positioned at an end portion of the rotation of the control knob. That is, the control knob provides infinite adjustment over a finite range so that the control knob actually rotates over a range of less than 360°.
In other arrangements, a cooking appliance can actually rotate through 360°. The control knob can either be rotated in a first direction to pass over the full temperature range, starting from a low setting and leading to a maximum setting, or the control knob can be rotated in a second direction to pass over the full temperature range, starting at the maximum setting and leading to the low setting. In many cases, the low setting is achieved by activating a single heating element, and the maximum setting is achieved by activating multiple heating elements.
For example, as shown in the one prior art arrangement illustrated in FIG. 1, it is known to rotate a control knob 2 counterclockwise from an off position 3 to initially set a low setting for a heating zone by activating a center heating element 4. Continued rotation of knob 2 raises a temperature of heating element 4 until additional heat is required, thus activating a second heating element 5. Further rotation of knob 2 causes a third heating element 6 to be activated to establish the maximum setting. Knob 2 can be continually rotated counterclockwise to an off position 3 or rotated clockwise back to off position 3. Alternatively, a consumer can elect to go straight from off position 3 to the maximum setting by simply rotating knob 2 in a clockwise direction. In any case, while effective at operating various heating elements 3–6, the overall adjustment scale is somewhat limited. In other words, the scale is not sensitive enough to enable precise control over the entire heating zone.
Based on the above, there still exists a need for a control element for a cooking appliance that provides a great degree of control over the operation of multiple heating elements associated with a particular heating zone. More specifically, there exists a need for a control element that, when rotated in a first direction, provides a large adjustment range for only one heating element and, when rotated in a second direction, provides a large adjustment range for multiple heating elements.